我试图弄清楚如何将商家集合扁平化,每个商家都包含一个订单集合到一个扁平的 OrderViewModel 列表。
这是我的 DTO:
public class Merchant
{
public string MerchantName { get; set; }
public List<Order> Orders { get; set; }
}
public class Order
{
public string OrderId { get; set; }
}
这是 View 模型:
public class OrderViewModel
{
public string MerchantName { get; set; }
public string OrderId { get; set; }
}
我的目标是将 List
var myMerchants = new List<Merchant>
{
new Merchant
{
MerchantName = "Merchant X",
Orders = new List<Order>
{
new Order { OrderId = "Order 1"},
new Order { OrderId = "Order 2"},
new Order { OrderId = "Order 3"}
}
},
new Merchant
{
MerchantName = "Merchant Y",
Orders = new List<Order>
{
new Order { OrderId = "Order 4"},
new Order { OrderId = "Order 5"},
new Order { OrderId = "Order 6"}
}
}
};
var models = Mapper.Map<List<OrderViewModel>>(myMerchants);
最佳答案
因为根对象的基数不是 1:1,(即 2 个根 Merchants
需要映射到 6 个 OrderViewModels
),您可能需要求助于一个custom TypeConverter
并在集合级别进行操作,您可以在其中使用 .SelectMany
进行展平:
public class MyTypeConverter : ITypeConverter<IEnumerable<Merchant>, List<OrderViewModel>>
{
public List<OrderViewModel> Convert(ResolutionContext context)
{
if (context == null || context.IsSourceValueNull)
return null;
var source = context.SourceValue as IEnumerable<Merchant>;
return source
.SelectMany(s => s.Orders
.Select(o => new OrderViewModel
{
MerchantName = s.MerchantName,
OrderId = o.OrderId
}))
.ToList();
}
}
然后你可以引导:
Mapper.CreateMap<IEnumerable<Merchant>, List<OrderViewModel>>()
.ConvertUsing<MyTypeConverter>();
然后这样映射:
var models = Mapper.Map<List<OrderViewModel>>(myMerchants);
关于c# - AutoMapper 展平嵌套集合,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/31284989/